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See detailApproximate and Efficient Methods to Assess Error Fields in Spatial Gridding with Data Interpolating Variational Analysis (DIVA)
Beckers, Jean-Marie ULg; Barth, Alexander ULg; Troupin, Charles ULg et al

in Journal of Atmospheric & Oceanic Technology (2014), 31(2), 515-530

We present new approximate methods to provide error fields for the spatial analysis tool Diva. It is first shown how to replace the costly analysis of a large number of covariance functions by a single ... [more ▼]

We present new approximate methods to provide error fields for the spatial analysis tool Diva. It is first shown how to replace the costly analysis of a large number of covariance functions by a single analysis for quick error computations. Then another method is presented where the error is only calculated in a small number of locations and from there the spatial error field itself interpolated by the analysis tool. The efficiency of the methods is illustrated on simple schematic test cases and a real application in the Mediterranean Sea. These examples show that with these methods one has the possibility for quick masking of regions void of sufficient data and the production of "exact" error fields at reasonable cost. The error-calculation methods can also be generalized for use with other analysis methods such as 3D-Var and are therefore potentially interesting for other implementations. [less ▲]

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See detailImportance of recent extreme weather variation in Djibouti and need for impact quantification
Nour Ayeh, Moustapha; Mahamoud, Ayan; Saad, Osman et al

Poster (2014, February)

This analysis shows that the current rainfall deficit is exceptional and historically unique. The significant population migration induced by the drought to Djibouti city must be supervised, especially ... [more ▼]

This analysis shows that the current rainfall deficit is exceptional and historically unique. The significant population migration induced by the drought to Djibouti city must be supervised, especially during their spontaneous settling. This presented example confirms that current rainfall shortages and increasing temperature extremes are impactinglocal people who urgently need adaptation and DRR strategies. It is necessary to reduce exposure to hydrological risks of these affected populations, in order that victims of the drought are not carried away by a rainfall excess. [less ▲]

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See detailPrecision synthesis of poly(ionic liquid)-based block copolymers by cobalt-mediated radical polymerization and preliminary study of their self-assembling properties
Coupillaud, Paul; Fèvre, Maréva; Wirotius, Anne-Laure et al

in Macromolecular Rapid Communications (2014), 35(4), 422-430

A poly(ionic liquid)-based block copolymer (PIL BCP), namely, poly(vinyl acetate)-b-poly(N-vinyl-3-butylimidazolium bromide), PVAc-b-PVBuImBr, is synthesized by sequential cobalt-mediated radical ... [more ▼]

A poly(ionic liquid)-based block copolymer (PIL BCP), namely, poly(vinyl acetate)-b-poly(N-vinyl-3-butylimidazolium bromide), PVAc-b-PVBuImBr, is synthesized by sequential cobalt-mediated radical polymerization (CMRP). A PVAc precursor is first prepared at 30 °C in bulk by CMRP of VAc, using bis(acetylacetonato)cobalt(II), Co(acac)2, and a radical source (V-70). Growth of PVBuImBr from PVAc-Co(acac)2 is accomplished by CMRP in DMF/MeOH (2:1, v/v). This PIL BCP self-assembles in the sub-micron size range into aggregated core–shell micelles in THF, whereas polymeric vesicles are observed in water, as evidenced by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Thin-solid sample cut from raw materials analyzed by TEM shows an ordered lamellar organization by temperature-dependent synchrotron small-angle X-ray scattering (SAXS). Anion exchange can be accomplished to achieve the corresponding PIL BCP with bis(trifluorosulfonyl)imide (Tf2N−) anions, which also gives rise to an ordered lamellar phase in bulk samples. A complete suppression of SAXS second-order reflection suggests that this compound has a symmetric volume fraction (f ≈ 0.5). SAXS characterization of both di- and triblock PIL BCP analogues previously reported also shows a lamellar phase of very similar behavior, with only an increase of the period by about 8% at 60 °C. [less ▲]

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See detailModalités prescriptives des nouveaux dispositifs de gestion et logiques identitaires des managers publics
Pichault, François ULg; Schoenaers, Frédéric ULg

in RH Publica : (2014), 4-2013(oct-nov-dec), 16-21

Les pouvoirs locaux sont soumis, comme tous les autres niveaux de pouvoir, à de profonds mouvements de « managérialisation », dont la récente transformation des titres de secrétaire communal et de ... [more ▼]

Les pouvoirs locaux sont soumis, comme tous les autres niveaux de pouvoir, à de profonds mouvements de « managérialisation », dont la récente transformation des titres de secrétaire communal et de receveur communal en directeur général et directeur financier sont des illustrations emblématiques. Les pouvoirs communaux sont désormais invités à rédiger des « programmes stratégiques transversaux » (PST) et à se doter de divers outils de gestion en vue d’améliorer le service aux citoyens dans un cadre budgétaire restreint. Le présent article propose une réflexion sur la capacité de ces nouveaux outils à façonner l’action publique au niveau du management intermédiaire… [less ▲]

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See detailImmunomodulatory effects of Rapamycin in xenogeneic GVHD
Ehx, Grégory ULg

Poster (2014, January 31)

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Several studies have shown that rapamycin (RAPA), an mTOR ... [more ▼]

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Several studies have shown that rapamycin (RAPA), an mTOR inhibitor with immunosuppressive properties, may reduce GVHD severity and mortality, notably by favoring regulatory T cells (Tregs) proliferation in vivo and in vitro. However, very few data have been reported about the global impact of this drug on the immune system in the context of GVHD. The present work investigates the cellular mechanisms by which RAPA delays death from xenogeneic GVHD induced by peripheral blood mononuclear cells infusion in NSG mice. Our results show that RAPA injections significantly delay death from xenogeneic GVHD and reduce disease severity. Flow cytometric analyses highlighted a strong reduction of human cells chimerism in mice together with higher CD4+/CD8+ T cells balance due to a lower proliferation of CD8+ T cells. In addition, the frequencies of naive CD4+ and CD8+ T cells were higher and the CD4+ T cells showed a reduced effector phenotype (CD45RO+CD27-). Tregs were positively affected as RAPA up-regulated their expression of Bcl-2 and Ki67 as well as their STAT5 phosphorylation level, leading to higher Treg frequency in treated mice. Altogether these data demonstrate that RAPA delays xenogeneic GVHD by lowering human chimerism and effector CD4+ frequency as well as promoting Tregs. [less ▲]

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See detailDroit constitutionnel - Dossier de documentation (année 2013-2014)
Behrendt, Christian ULg

Learning material (2014)

Le document constitue le Dossier de documentation, à lire par les étudiants en parallèle au cours ex cathedra, de l'enseignement de Droit constitutionnel dispensé à l'Université de Liège en 2e année de ... [more ▼]

Le document constitue le Dossier de documentation, à lire par les étudiants en parallèle au cours ex cathedra, de l'enseignement de Droit constitutionnel dispensé à l'Université de Liège en 2e année de bachelier en droit et en 2e année de bachelier en science politique. En plus du dossier de documentation, les étudiants sont par ailleurs invités à lire, au titre de la matière à connaître pour l'examen, l'ouvrage "L'action du Roi en Belgique depuis 1831" de Jean Stengers (Bruxelles, Racine, 3e édition, 2008). [less ▲]

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See detailLandesbeitrag Belgien : Wesen und Gestalt der Verfassungsgerichtsbarkeit in Belgien
Behrendt, Christian ULg

in von Bogdandy, Armin; Grabenwarter, Christoph; Huber, Peter M. (Eds.) Ius Publicum Europaeum - Band VI - Verfassungsgerichtsbarkeit (2014)

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See detailAn exact bi-directional dynamic programming algorithm for an elementary shortest path problem with variable service start time
Arda, Yasemin ULg; Crama, Yves ULg; Kucukaydin, Hande ULg

Conference (2014, January 31)

We consider an elementary shortest path problem with resource constraints (ESPPRC), where a capacitated single vehicle serves customers by respecting their associated time windows. The vehicle can start ... [more ▼]

We consider an elementary shortest path problem with resource constraints (ESPPRC), where a capacitated single vehicle serves customers by respecting their associated time windows. The vehicle can start servicing the customers at any desired time, but it can be used for a fixed amount of time. The total transportation cost depends on the total distance traveled and the total amount of time that the vehicle spends by performing the assigned trip. On the other hand, each served customer yields a revenue. Thus, the aim is to identify the path to be followed and the start time of the vehicle from the depot that minimize the total transportation cost minus the gained revenues. This kind of a problem can be encountered as a pricing subproblem when a branch-and-price algorithm is applied to solve vehicle routing problems with additional constraints. In such a case, the revenues correspond to the dual prices of the visited vertices. It is known that the classical ESPPRC can be solved to optimality by implementing a dynamic programming (DP) algorithm. However, our problem has to take an infinite number of Pareto-optimal states into consideration, since the vehicle can leave the depot at any point in time and charges depending on the total traveling and waiting time. We propose an exact DP algorithm which can deal with an infinite number of Pareto-optimal states by representing total traveling and waiting time as a piecewise linear function of the service start time at the depot and develop suitable dominance rules. Furthermore, a column generation algorithm is devised for solving the relaxed set covering formulation of the related vehicle routing problem where new columns are determined by the proposed DP algorithm. Finally, computational results are presented. [less ▲]

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See detailHomogenization with propagation of instabilities through the different scales
Noels, Ludovic ULg; Wu, Ling ULg; Nguyen, Van Dung ULg et al

Scientific conference (2014, January 31)

In this work, multi-scale methods with strain softening are developed in the contexts of damage modeling for composite laminates and of buckling analyses in cellular materials. First, an anisotropic ... [more ▼]

In this work, multi-scale methods with strain softening are developed in the contexts of damage modeling for composite laminates and of buckling analyses in cellular materials. First, an anisotropic gradient–enhanced continuum damage model is embedded in a mean–field homogenization (MFH) process for elasto-plastic composites. The homogenization procedure is based on the newly developed incremental secant mean-field homogenization formulation, for which the residual stress and strain states reached in the phases upon a fictitious elastic unloading are considered as starting point to apply the secant method. The mean stress fields in the phases are then computed using isotropic secant tensors, which are naturally used to define the Linear Comparison–Composite The resulting multi– scale model is then applied to study the damage process at the meso–scale of laminates, and in particular the damaging of plies in a composite stack. By using the gradient–enhanced continuum damage model, the problem of losing uniqueness upon strain softening is avoided. Second, an efficient multi–scale finite element framework capturing the buckling instabilities in cellular materials is developed. As a classical multi–scale computational homogenization scheme loses accuracy with the apparition of the macroscopic localizations resulting from the micro–buckling, the second order multi–scale computational homogenization scheme is considered. This second–order computational framework is enhanced with the following novelties so that it can be used for cellular materials. At the microscopic scale, the periodic boundary condition is used because of its efficiency. As the meshes generated from cellular materials exhibit a large void part on the boundaries and are not conforming in general, the classical enforcement based on the matching nodes cannot be applied. A new method based on the polynomial interpolation2 without the requirement of the matching mesh condition on opposite boundaries of the representative volume element (RVE) is developed. Next, in order to solve the underlying macroscopic Mindlin strain gradient continuum of this second–order scheme by the displacement–based finite element framework, the treatment of high order terms is based on the discontinuous Galerkin (DG) method to weakly impose the C1-continuity. Finally, as the instability phenomena are considered at both scales of the cellular materials, the path following technique is adopted to solve both the macroscopic and microscopic problems. [less ▲]

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See detailSpectrometric monitoring of atmospheric carbon tetrafluoride (CF4) above the Jungfraujoch station since 1989: evidence of continued increase but at a slowing rate
Mahieu, Emmanuel ULg; Zander, Rodolphe ULg; Toon, G. C. et al

in Atmospheric Measurement Techniques (2014), 7

The long-term evolution of the vertical column abundance of carbon tetrafluoride (CF4) above the high-altitude Jungfraujoch station (Swiss Alps, 46.5° N, 8.0° E, 3580 m a.s.l.) has been derived from the ... [more ▼]

The long-term evolution of the vertical column abundance of carbon tetrafluoride (CF4) above the high-altitude Jungfraujoch station (Swiss Alps, 46.5° N, 8.0° E, 3580 m a.s.l.) has been derived from the spectrometric analysis of Fourier transform infrared solar spectra recorded at that site between 1989 and 2012. The investigation is based on a multi-microwindow approach, two encompassing pairs of absorption lines belonging to the R-branch of the strong ν3 band of CF4 centered at 1283 cm−1, and two additional ones to optimally account for weak but overlapping HNO3 interferences. The analysis reveals a steady accumulation of the very long-lived CF4 above the Jungfraujoch at mean rates of (1.38 ± 0.11) × 1013 molec cm−2 yr−1 from 1989 to 1997, and (0.98 ± 0.02) × 1013 molec cm−2 yr−1 from 1998 to 2012, which correspond to linear growth rates of 1.71 ± 0.14 and 1.04 ± 0.02% yr−1 respectively referenced to 1989 and 1998. Related global CF4 anthropogenic emissions required to sustain these mean increases correspond to 15.8 ± 1.3 and 11.1 ± 0.2 Gg yr−1 over the above specified time intervals. Findings reported here are compared and discussed with respect to relevant northern mid-latitude results obtained remotely from space and balloons as well as in situ at the ground, including new gas chromatography mass spectrometry measurements performed at the Jungfraujoch since 2010. [less ▲]

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See detailDu Bengale à la Nouvelle Angleterre (en passant par l'Inde): Trajectoires transnationales et mémoires transrégionales dans "The Lowland" de Jhumpa Lahiri
Munos, Delphine ULg

Scientific conference (2014, January 31)

Comme son titre le suggère déjà, le dernier roman de l’auteur bengali-américain Jhumpa Lahiri, The Lowland (« La Basse Terre »), traite moins de la vie d’hommes et de femmes qu’il ne parle d’espace et de ... [more ▼]

Comme son titre le suggère déjà, le dernier roman de l’auteur bengali-américain Jhumpa Lahiri, The Lowland (« La Basse Terre »), traite moins de la vie d’hommes et de femmes qu’il ne parle d’espace et de géographie, et plus particulièrement, de la façon dont certains paysages peuvent se substituer à l’Histoire, quand cette dernière n’arrive plus à ‘porter’ ses zones d’ombre, ses propres impensés. Comme son titre ne l’indique pas, cette fois, The Lowland prend pour sujet les répercussions de l’Indépendance indienne, à Calcutta et au-delà, à travers les destinées entrecroisées de deux frères, Udayan et Subhash – le premier qui embrasse la révolution armée d’obédience maoïste et la cause des Naxalites, avec des conséquences dramatiques, le deuxième qui choisit de s’exiler aux Etats-Unis pour ses études, moins par ambition personnelle ou en raison de la grande instabilité politique de Calcutta dans les années 60 et 70, d’ailleurs, que pour enfin se donner le droit de rivaliser d’audace avec son frère cadet. Si j’ai choisi The Lowland pour aborder le sujet des enjeux esthétiques et spirituels de la commémoration, c’est justement parce que dans le dernier roman de Lahiri (paru en septembre 2013 et non encore traduit en français), la thématique historique est omniprésente, bien qu’elle reste en sourdine, perpétuellement soumise à une esthétique du détour, du déplacement, et du non-dit, qui trouvera son apogée (et, pour Subhash, une certaine forme de rédemption spirituelle) dans ce que l’on pourrait appeler l’émergence d’une topographie transnationale – et bien plus, transrégionale – de l’impensé historique. [less ▲]

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See detailLe dispositif carcéral : visages, corps et… liberté
Englebert, Jérôme ULg

Scientific conference (2014, January 31)

Detailed reference viewed: 37 (6 ULg)
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See detailQuestions de droit pénal social - Petit état de la jurisprudence
Michiels, Olivier ULg

Conference (2014, January 31)

L'exposé portait sur les points suivants : L’obstacle à la surveillance Lien de subordination Les infractions règlementaires Le moyen tiré de la violation par l’article 5 de la loi du 4 août 1996 du ... [more ▼]

L'exposé portait sur les points suivants : L’obstacle à la surveillance Lien de subordination Les infractions règlementaires Le moyen tiré de la violation par l’article 5 de la loi du 4 août 1996 du principe de légalité L’article 128, 1° du Code de droit pénal social Cumul des allocations et non bis in idem La condamnation d’office au triple des cotisations éludées La libre circulation des travailleurs provenant d’un nouvel Etat membre de l'Union Le mandataire ad hoc Le concours entre infractions de droit commun et de droit pénal social [less ▲]

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See detailPerformances littéraires et genre: proposition à partir de la notion d’ethos à travers une lecture de The Brief Wondrous Life of Oscar Wao de J. Díaz.
Berlage, Pauline ULg

Conference (2014, January 31)

Face la population transnationale d’origine latino-américaine croissante à travers le monde – spécialement présente en Espagne et aux États-Unis – je me suis intéressée à la création littéraire en tant ... [more ▼]

Face la population transnationale d’origine latino-américaine croissante à travers le monde – spécialement présente en Espagne et aux États-Unis – je me suis intéressée à la création littéraire en tant que mise en récit de Soi et de l’Autre. Dans le cadre de cette littérature latinoaméricaine de la migration, je me centrerai sur la représentation du genre dans ces romans, c'est-à-dire sur ces attitudes performatives qui (re)produisent les normes et les modèles mais aussi parfois des corps a-normatifs et illisibles (Butler, T. de Lauretis). Je proposerai donc d’articuler la notion stimulante de performance de genre telle que proposée par J. Butler à celle d’ethos rhétorique (Amossy, Maingueneau) dans le but d’analyser la voix narrative du roman The Brief Wondrous Life of Oscar Wao de Junot Díaz (2008). Cette lecture nous permettra de mettre en lumière le jeu de va-et-vient par rapport aux stéréotypes de genre qui font autorité et, plus fondamentalement, la construction d’un corps queer apatride qui s’oppose "naturellement" au corps masculin de la diaspora. [less ▲]

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See detailLight modulates cognitive brain functions
Vandewalle, Gilles ULg

Scientific conference (2014, January 31)

Detailed reference viewed: 30 (1 ULg)